Door lift mechanism



June 29, 1954 Filed Feb. 5, 1952 S. O. CHRISTENSEN DOOR LIFT MECHANISM 2Sheets-Sheet l Sg NEY 0. CHR/S TENSEN June 29, 1954 s. o. CHRISTENSEN2,682,076

DOOR LIFT MECHANISM Filed Feb. 5, 1952 2 Sheets-Sheet 2 Fla- 5 INVENTOR.

; SggNEYQ Cu /s TENSEN Patented June 29, 1954 .Sidney O.'.Christensen,Jamaica, to American Car, and Foundry N. Y., assignor Company, New

York, N Y., a-corporation of NewJersey Application-February 5,1952,.Serial No. 270,079 g 2' Claims. 1

This-invention relates, to lift mechanism for a -,car door and moreparticularly to mechanism for elevating, and-shifting the door.longitudinally by H .a single operation requiring littlev physicaleffort.

The invention-comprises, the novel structure -...and combination ofpartsthereinafterdescribed and moreparticularly pointed. out anddefinedin .the appended claims.

.In the accompanying-drawings which illustrate a preferred form of theinvention:

Fig. l is a side-;.elevation of a door. and lift .mechanismassociatedwith a portion-of aside taken online 4'4- of Fig. 3; showing a'portionof the actuator'for' the lift mechanism.

Fig; 5' is asectional view through. thedoor,

taken on--line 5 5 of F'ig. 3 showinguoneyofthe "door supporting rollers-a-nd-'lift 'leverstructures.

Fig. 6 is a sectional view through the door, taken on line E-'5 of Fig.3, showing one of the lift lever structures and its guide.

Referring now to the drawings by characters of reference, the box carside wall is provided with opening ll. Door supporting track I2 issecured to the outside of the Wall and extends below the side wallopening and beyond the sides thereof. Door I3 is mounted to be liftedand moved longitudinally on the track into positions covering anduncovering the opening. Conventional guide and retainer structures I4are associated with the top of the door and the adjacent car side wall.

The door can be formed in a conventional manner with a suitable frameand panel wall structure. The preferred form of door includes a hollowlower frame structure or housing having a bottom wall i5, forfrictionally engaging the track, side flanges l6 and I! extendingupwardly from the bottom wall and an inner closure plate 18. Corrugatedmetal panel I9 forms the vertical wall of the door and is secured alongits lower edge to the top portion of the outer flange [6 of the lowerframe housing by rivets 8. A T-shaped metal mounting plate 8 is arrangedin the lower housing and its head portion is secured to the upper end offlange l6 by rivets 8. The leg portion of plate 9 extends adjacent coverplate l8, in spaced relation with flange l6, and the cover plate It issecured to flange I! and panel [9 by suitable means, such as welding.

2 U '1' The weight of the door normally causes the base wall; E of thelower housing to rest on. and frictionally engage track i2. "Manually;operable mechanism is associated with the door for lifting 5 .it abovethe track and for moving it along the track longitudinally of the car tocover or uncover the wall door opening.

"The lift structure is. mounted within the lower door base housing. andincludes a shiftable T- 10 shaped bar 2%: providedwith endextensionseach comprised of a pair of smaller spaced angle members or brackets 2!having a, horizontal arm secured torthe bar and a right-angularlyupstanding arm- Lower rollers 22 are arranged between the .pairs ofvextensions and are provided with bearings 22 mounted on shafts 23carriedby the outer, ends of the. horizontal arms, and upper cammingrollers 26 are arranged between the pairs of extensions and are mountedonshafts 25carried bythe upperends of the vertical arms. The 7 lowerhousing base walli 5 is formedwith slots. 26 sothatrollers 22, whichnormally lie within the .base housing,.,can,be projected to-bcar ontrack l2; Bearing members 27 are secured by rivets 8 to panel 19 andeach has a bottom flange formed with oppositely extending inclined anglebearing faces 28. Members 38 are secured by rivets 38 to flange I6 ofthe door base housing and are spaced to receive and guide the bar 20adjacent its ends. The lift bar 20 is moved longitudinally in eitherdirection by manually operable shift mechanism comprising hand leverfixed on a flat end 3| of shaft 32 from which arm 33 depends. This armhas an inturned lower end 34, or trunnion, pro- 35 jecting into centralvertical slot 35 in the lift beam 20.

The weight of the door will normally cause the base wall it; to rest onthe track and in such position of the door rollers it will lie in theapex of the camming faces 28 and rollers 22 will engage the track. Asthe hand lever 30 is shifted in either direction away from uprightposition, trunnion 34 will swing in an are against the adjacent bar walland will shift the lift structure longitudinally in the door causing thelift structure rollers FM to ride longitudinally along inclined surfacesof members 21 and thereby cam the door upwardly. Due to the angularityof the bearing faces 28, rollers 24 will act uniformly on each endportion of the door when the lift structure is shifted longitudinally ineither direction. While the door is lifted, it can be moved on rollers22 along the track to desired position by manual pressure exertedagainst the lever 30.

The invention may be modified in various re- 3 spects as will occur tothose skilled in the art and the exclusive use of all modifications ascome within the scope of the appended claims is contemplated.

What is claimed is:

1. In a railway box car having a door supporting track on one side wallbeneath a door opening, the combination with a door having a nousingcoextensive with the lower portion thereof formed with a bottom walladapted to normally rest on the track and having slots therein, of a barmounted within said door housing and shiftable longitudinally thereof,bearing members within the housing fixed to the door each havingoppositely downwardly inclined cam faces, angle-shaped brackets fixed tothe ends of said bar having horizontally extending arms andright-angularly upstanding arms, door supporting rollers carried by thehorizontally extending arms of said brackets adapted to be projectedthrough the slots in the bottom wall of said door housing to engage saidtrack, camming rollers carried by the upstanding arms of said bracketsnormally engaging the apex of said camming faces of said bearingmembers, a rock shaft journalled in the door housing centrally abovesaid longitudinally shiftable bar, said bar having a central verticalslot therein, an arm integral with and depending from said rock shaft,said arm being formed with an inwardly extending trunnion engaged insaid vertical slot of the bar, and a hand lever fixed to said rock shaftand swingable in opposite directions to shift said bar longitudinallywhereby said camming rollers will ride on said inclined cam faces ofsaid bearing members to lift the door to a position in which it issupported on said track rollers engaging said track through the slots inthe bottom wall of said door housing.

2. In a railway box car having a door supporting track on one side wallbeneath a door opening, the combination with a door having a housingextending along the lower portion thereof formed with a bottom walladapted to normal- 4 1y rest on the track and provided with slotstherein, of a T-shaped bar located within the door housing and shiftablelongitudinally thereof, bearing members secured within the housing onthe door formed with inverted V-shaped camming faces, angle-shapedbrackets fixed to the ends of said bar having horizontally extendingarms and right-angularly extending upright arms, door,

supporting rollers carried by the horizontal arms of said bracketsadapted to be projected through the slots in the bottom wall of saiddoor housing to engage the track, angle plates fixed to the outer wallof said door housing and having depending spaced-apart guide portionsbetween which said longitudinally shiftable T-shaped bar is arranged,camming rollers carried by the upright arms of said brackets normallyengaging the apex of said camming faces on said bearing members, a shaftrotatably mounted in the door housing centrally above said bar, said barbeing formed with a central vertical slot therein, an arm depending fromsaid shaft formed with an inwardly extending trunnion engaged in thevertical slot of said bar, and a hand operating lever fixed to saidshaft exteriorly of the door housing swingable in opposite directions toshift said bar longitudinally whereby to move said camming rollers inbearing engagement with said camming faces of the bearing members, saidengagement of the camming rollers with the camming faces of the bearingmembers forcing said door supporting rollers through said slots of saiddoor housing bottom wall into track engaging position to lift the doorthereon.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,720,898 Heinen et al July 16, 1929 2,047,421 Madland July14, 1936 2,058,742 Tobin Oct. 27, 1936 2,090,189 Ditchfield Aug. 17,1937 2,373,447 Beauchamp Apr. 10, 1945 2,494,467 Beauchamp Jan. 10, 1950

